Experimental Study of the Hydrodynamic Loads on High Speed Planing Craft

Abstract

Slamming pressure assessment is an important topic for shell plating and stiffener design of bow flare. In this study, the pressure distribution on the bottom plating of an high speed planning craft is evaluated through measurements of the impact pressures on scale model running in regular waves. The planing hull model, monohedral hard chine built with clear bottom and deck, in order to allow the visual inspection of the fluid flow and the exact points of impact has been extensively studied as reported in previous works. From the time histories of vertical motions (heave and pitch) and bow acceleration of the model measured in “standard” seakeeping tests, preliminary assessment of the slamming impact pressure according to Zhao and Faltinsen method is performed. The experimental campaign presented in this paper is focused on the pressure field assessment in nine points of the hull bottom surface running at four velocities and two regular waves. Results analysis in time and frequency domain is given, identifying the pressure distribution along the bottom panel. Furthermore, comparison of measured, analytical and normative values has been performed. From the cross-correlation of measured responses further comments and indications for future work has been withdrawn. The reported results provide an useful data set for all transportation-engineering systems under dynamic load.